package com.j3.string;

import java.util.Random;

public class RandomString {

	private static final Random RANDOM = new Random();
	public static String randomStrWithLen(int len) {
		StringBuilder builder = new StringBuilder(len);
		for (int i = 0; i < len; i++) {
			builder.append(RANDOM.nextInt(10));
		}
		return builder.toString();
	}
}
